7 spd on 8 spd hubs

[Tel]

I've got a dilemma. I have a cyclo cross bike and have just acquired a set of 8/ 9 speed ultegra hubs on open pro rims which fit it a treat. I have a set of Sora 7 speed + double STI shifters which I'd like to use instead of the bar end shifters that I currently have but obviously these won't work with an 8 or 9 speed cassette. Can I fit a 7 spd cassette on the hubs, perhaps with the use of an extra spacer? Also will the left lever work a triple rather than a double front mech?

I don't really want to pay out £150+ on new shifters, what do you reckon I should do?

 

[fossyant]

Yes you can, and I do that on two of my bikes. - One runs new Deore hubs -needs 2 3mm spacers, the Mavic Ksyrium's with 2 x 3mm spacers, then the 7 speed cassette.

You'll need 1 or 2 of the 3mm spacers on the spoke side, then fit the 7 speed cassette. You may need an additional 1mm spacer if you can't tighten it on the 1 x 3mm spacer - if you don't have one spare..PM me... - PS if you've had lots of 7 speed cassettes, you'll have a spacer some where...

 

[fossyant]

PS the spacers, are the plastic or alloy bits between the sprockets. If your cassette comes screwed together, just use a small allen key and get rid,,then you can swap and change.

7 speed is supposed to be 3.1mm and 8 speed 3mm - never noticed any difference using 3mm on the lot, or indeed 3.1, but I've got a load of blingy Dura Ace polished alloy spacers that I'm using on my 3 geared bikes....all 3mm 8 or 7 speed.

 

[Landslide]

Also will the left lever work a triple rather than a double front mech?

I think it depends on the age. I've got some older ones (2002?) and at that time you had to buy double or triple. I've a sneaking suspicion that later models would work on either, but I'm not sure. Try yours out with a spare cable and see what the score is.

 

[TheDoctor]

You can buy a specific spacer to fit 7 speed cassettes to 8/9 speed hubs. They're only a couple of pounds - merlin do them and so do lots of others - that was just the first hit on Google.

 

[Tel]

Excellent! Thanks guys and thanks for the offer fossy, I think I've got some spare spacers though but thanks again.

That is very likely what I'll do then, however I do now have another option and that is to fit a set of Suntour Command shifters (as fitted to this rather tasty Karate Monkey http://james.architectureburger.com/cycle/skm.html) which I have kicking about, they'll have to be used in friction mode although it doesn't take long to get used to smooth shifting with them, then perhaps I'll bring my old Ultegra 600 equipped Raleigh into this century with the Sora STI's as thats 7 speed and a double. Hmm decisions, decisions